The mRNA expression of the collagenase MMP13 was not significantly increased 10 days after infection, whereas the expression of the endogenous inhibitor TIMP1 was significantly increased (WT: 37.42 ± 17.78 fold, P = 0.0043; STAT3 KO: 51.59 ± 28.97 fold, P < 0.0001) which is then reduced to an only slightly increased expression 28 days after infection (WT: 3.07 ± 0.93 fold, P = 0.2168; STAT3 KO: 4.47 ± 1.54 fold, P = 0.0485) and revealed no distinction between WT and STAT3 KO mice. The gene discussed is MMP13; the disease is infection.